• Journal of Korean Society for Atmospheric Environment
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• v.8 no.3
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• pp.179-190
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• 1992

This study was carried out to characterize sources of atmospheric total suspended particulates (TSP) in urban and sub--urban areas of metropolitan taegu. The sources were tentatively identified by a multivariate technique, i.e. principal component analysis (PCA), and the source contributions to the atmospheric concentrations of TSP were further estimated by stepwise multiple regression analysis. A total of 5 sources was identified in the urban area of Taegu (soil dust resuspension, fuel combustion, secondary aerosol, traffic related aerosol, and refuge burning), while 4 sources were found to be significant in the sub--urban area as following: fuel combustion/secondary aerosol, soil dust resuspension, traffic related aerosol, and wood/agricultural burning. The largest contributor to the atmospheric TSP appeared to be the soil dust resuspension in both areas. The source apportionment of the extractable organic matter (EOM) was also carried out for the Taegu data. The EOM was determined with respect to the solvent polarity, i.e. cyclohexane (non-polar), dichloromethane (semi--polar), and acetone (polar). In addition, the source profiles for the TSP in Taegu area were estimated using a PCA-based algorithm, and the validity was evaluated tentatively by comparing the data in the literature.

• Journal of environmental and Sanitary engineering
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• v.14 no.4
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• pp.158-164
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• 1999

This study was carried out to investigate total suspended particulates (TSP) in Iksan area collected by nine stages Anderson air sampler and High volume air sampler from Jul. 1996 to Jul. 1998.The results are as follows1. The average of TSP concentration to be collected by Anderson air sampler and High volume air sampler in Iksan city are $59{\mu}g/m^3$, $67{\mu}g/m^3$. It was below the level of environmental standard. 2. The average of TSP concentration by measured method are HVAS > AS > Gov. 3. The average of TSP concentration on seasonal change are higher spring than winter. It were $65.5{\mu}g/m^3$ of Spring, $57{\mu}g/m^3$ of Summer, $52.5{\mu}g/m^3$ of Fall, $61{\mu}g/m^3$ of Winter. 4. Particle size 3istribution of atmospheric particulate was divided into two groups, coarse group was made by particles larger than $1.1-2.1{\mu}m$ in diameter and fine groups smaller than $1.1-2.1{\mu}m$ in diameter. about 50% of total suspended particle measured by Anderson air sampler during the sampling period was coarse particle.

• Journal of Environmental Health Sciences
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• v.22 no.3
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• pp.64-71
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• 1996

Measurement of concentration and size distribution of TSP, ammonium, nitrate and sulfate were made from Mar., 1991. to June., 1992 in Seoul. The seasonal variation of concentration and size distribution of aerosols has been investiated. Aerosol were collected and size frationated by Andersen air sampler. Size classified samples were extrated with deionized water and analyzed for ammonium, nitrate and sulfate by ion chromatography. As the results of measurement, the average of concentration and MMAD(mass median aerodynamic diameter) were $118.58 \mu g/m^3$, and $2.77 \mu m$ for TSP, $1.92 \mu g/m^3$ and $1.35 \mu m$ for ammonium, $1.34 \mu g/m^3$ and $1.58 \mu m$ for nitrate, $8.52 \mu g/m^3$ and $2.15 \mu m$ for sulfate. The Seasonal variation of concentration and size distribution was observed for ammonium, nitrate and sulfate. The concentration peak of TSP was observed in coarse particles in spring and observed in fine particles in winter. The concentration's distribution of TSP, ammonium, nitrate and sulfate was observed bimodal type during all season.

• Journal of Korean Society for Atmospheric Environment
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• v.7 no.1
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• pp.17-22
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• 1991

Total suspended particulates (TSP) in the atmosphere was collected and size-fractionated by Andersen high volume air sampler for one year (Mar. 1987 $\sim$ Feb. 1988) in Seoul. The concentrations of several polycyclic aromatic hydrocarbons and heavy metals were determined to investigate the atmospheric concentrations, seasonal variations and its relationship with the size distribution of suspended particulate matter. The arithmetic mean concentration of total suspended particulates was 200.44 $\mug/m^3$. The concentrations of heavy metals were 2433.80 for Fe, 629.49 for Zn, 600.71 for Pb, 143.87 for Cu, and 107.21 $ng/m^3$ for Mn, respectively. The concentrations of PAHs were 3.83 for benzo(a) pyrene, 2.95 for benzo(k)fluoranthene, and 4.42 $ng/m^3$ for benzo(ghi)perylene, respectively. PAHs, Pb and Zn abounded in particles below 2.0 $\mu$m, while Fe and Mn aboounded in particles above 2.0 $\mu$m. TSP and its chemical compositions showed the seasonal variations. The concentrations of anthrophogenic pollutants like TSP, PAHs and heavy metals in the fine particles were highest in winter and lowest in summer. PAHs and Pb analyzed showed significant correlations between each other and between TSP concentration in fine particles, indicating that the particles in which they are contained have a similar behavior in the atmosphere.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.2
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• pp.157-166
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• 2006

Ambient TSP at four sites in Korea and soil samples from the source regions of Asian Dust in northern China were collected and analyzed for 15 metal components and 6 water-soluble ions to conduct a chemical mass balance (CMB). CMB receptor model was used to estimate the source contribution of TSP during the Asian Dust period, and the model results showed that China soil was the largest source contributor, accounting for 81% of TSP ($458.2{\mu}g/m^3$). Vehicle emission and geological sources contributed to about 8.8% and 4.4% of aerosol mass, followed by sea salt (1.5%) and secondary aerosol (2.9%). Fuel combustion and industrial process sources were found to be relatively minor contributors to TSP (${\leq}1%$). In addition to source contribution estimates, this study tried to identify the origin of Asian Dust observed in Korea. Among all 13 China soil profiles presented in this study, the most adoptable profile which can project the case well was selected and considered as the origin of the applied case.

• International Journal of Computer Science & Network Security
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• v.21 no.4
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• pp.33-40
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• 2021

The traveling salesman problem (TSP) is one of the well-known and extensively studied NPC problems in combinatorial optimization. To solve it effectively and efficiently, various optimization algorithms have been developed by scientists and researchers. However, most optimization algorithms are designed based on the concept of improving route in the iterative improvement process so that the optimal solution can be finally found. In contrast, there have been relatively few algorithms to find the optimal solution using route construction mechanism. In this paper, we propose a route construction optimization algorithm to solve the symmetric TSP with the help of ratio value. The proposed algorithm starts with a set of sub-routes consisting of three cities, and then each good sub-route is enhanced step by step on both ends until feasible routes are formed. Before each subsequent expansion, a ratio value is adopted such that the good routes are retained. The experiments are conducted on a collection of benchmark symmetric TSP datasets to evaluate the algorithm. The experimental results demonstrate that the proposed algorithm produces the best-known optimal results in some cases, and performs better than some other route construction optimization algorithms in many symmetric TSP datasets.

• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.529-539
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• 2016

Modeling can be used to understand the atmospheric dispersion of air pollutants scientifically. Recent development of model computation enabled to simulate more diverse area. As flowing out from the emission source, the concentration profiles of air pollutants could be estimated in three dimensional space. This study used CALPUFF diffusion model to predict the diffusion of discharged NO2 and TSP on the atmosphere near a combined heat power plant and incinerator. It was investigated contribution concentration of the surrounding area by sources by comparing the actual measurement results and the results of the modeling. Contribution of emission sources to the local level of NO2 was found quite high particularly at the site, A-3. The estimated results by modelling revealed more significant effect on TSP at A-5.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.1
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• pp.81-90
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• 1986

Hanna - Gifford Model and Air Quality Display Model(AQDM) were validated in the simulation of $SO_2$ and TSP concentrations of Seoul City. The observed data which were measured at 16 sites of air monitoring system conducted by Seoul metropolitan city in 1984 were compared with the simulated data and the results were obtained as follows; 1. Several different meteorological data were examined: The particularities of meteorological data was not an influencing factor in the validity of simulation. The simulations of $SO_2$ by Hanna - Gifford model and by AQDM showed close correlation coefficients between the observed data and the simulated data (r = 0.71 - 0.78). 2. The simulation models showed different validities with the seasonal variation: The correlation coefficients (r) between the observed and the simulated by Hanna - Gifford Model for $SO_2$ and TSP were 0.86 and 0.80 in Spring, 0.63 and 0.66 in Summer, 0.76 in Autumn and 0.81 and 0.93 in Winter respectively. Those by AQDM were 0.73 and 0.68 in Spring, 0.56 and 0.79 in Summer, 0.77 and 0.76 in Autumn and 0.64 and 0.68 in Winter respectively. 3. The simulated data by two models had a close relationships: The correlation coefficients between them were 0.96 for $SO_2$, and 0.93 for TSP. With the above results, the application of models was discussed; Hanna - Gifford model was less valid in the simulation for the air quality of $SO_2$ and TSP in Seoul in Summer and AQDM also was not valid for $SO_2$ in Summer and in Winter and for TSP in Spring.

• Journal of Korean Society of Transportation
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• v.24 no.6 s.92
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• pp.103-117
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• 2006

This study develops an agent-based simulation model to evaluate tourist information systems under ubiquitous environment. In this study, individual tourist's activity chaining behavior is formulated as a utility maximization problem. The underlying assumption of the model is that tourists increase their activities within their time and budget constraints to maximize their utilities. The model seeks individual's optimal tour schedule by solving Prize-Collecting Multiple-Day Traveling Salesman Problem(PC MD TSP). The simulation-based evaluation framework allows investigating individual utility gains by their information type and the total expenditure at each tour attractions. The real-time tour activity scheduling system enables tourists to optimize their tour activities by minimizing their time loss and maximizing their opportunity to use high utility facilities.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.1
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• pp.93-100
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• 2003

In this technical information, the long-term measurement data at Gosan between 1992 and 2001 are analyzed with various statistical methods. First. it was confirmed that the basic assumption of t-test is important to classify data correctly. Second, it was founded that the difference of the number of data per month can affect the averaged concentration. Third, by using a non-parametric statistical method long term trend of aerosol composition free from seasonal effects is obtained.